Centrifugal vacuum pump



March 29, 192?.

WHW

K. G. SOMMER CENTRIFUGAL VACUUM PUMP Filed March 23, 1925 4 Sheets-Sheet l March 29, 1927.

K. G. SOMMER CENTRIFUGAL VACUUM PUMP Filed March 23. v1925 4 sheets-sheet a llllll '1,622,355' March 29, 1927 K, G. SOMMER CENTRIFUGAL VACUUM PUMP Filed March '25, 1925 4 Sheets-Sheet 5 @n E? @S FGA 5 March 29, 1927.4 1,622,355

lK. G. SOMMER CENTRIFUGAL VACUUM PUMP Filed March 25. 1925 4 Sheets-Sheet 4 I l I l Patented Maf. 29, i927.

UNITED STATES PATENT OFFICE.

KARL Gu-SOMMER, 0F BATTLE CREEK, MICHIGAN, ASSIGNOR T0 AMERICAN STEAM PUMP COMPANY, 0F BATTLE CREEK, MICHIGAN, `A CORPORATION 0F MICHIGAN.

CENTRIFD'GAL VACUUM PUMP.

Application led'larch 23, 1925. Serial No. 17,632.

This invention is an improvement in so called centrifugal vacuum pumps, and its principal object is to provide a pump simple in construction, efficient and economical inoperation, and capable'of drawing in a large amount of air or producing high suction without consuming a great deal of power. A further object is to aprovide a -centrifugal vacuum pump which is positive in its action, will deliver large-,volumes of air without pulsation, and which will be absolutely reliable. A still further object is to provide a centrifugal vacuum pump whose efficiency will be maintained foran indefinite period, and which can be driven by a high speed electric motor or any suitable device.

In the accompanying drawings, I have illustrated one practical form of pump embodying the invention, and one practical use thereof;A and-I will explain the invention with reference thereto, and summarize in the claims the essentials of the invention, the novel features of construction, and novel combinations rof (parts, for all of which protection is desire In said drawings: y i

Figure 1- is a vertical section through the pump on the line 1 1, Figure 2.l

Figure 2 is an enlarged transverse vertical longitudinal section through the pump on the line. 2 2, Figure 1.

Figure 3 is'an enlarged horizontal longitudinal section through the -pump on thep line 3 3, Figure 1.

Figure 4 is" a `detail vertical .section through one of the side castings or heads of the pump on theline 4 4, Figure 6.

Figure 5 is an enlarged vertical section through the rotordetached.

Figure 6 is an outer side view of one *of the side castings or head of the pump. Figure `7 is an outer View of the opposite side casting or head of the pump.

As shown in the drawing, the pump comprises a casing 1, and a rotor or ruimer 3 mounted on a shaft S, the runner and shaft being` the only moving or rotatingparts.

The casing 1 comprises a body casting 1a and opposite castings or heads 2 securely fitted and attached to opposite sides of the body casting 1*. The castin 1 has an approximately central cylindric chamber, A'in which is fitted .the rotor or impeller 3 and 1s provided exterior to the rotor with a volute passage 1b extendingA about half way around. the otor and communicating with a water discharge passage 1c in an upward extension of the body casting. Above the rotor 3 and opposite the volute chamber 1b, 1n the bod casting, is a smaller air and water cham er 1d which communicates with a passage 1?. ,The body casting also has ea port 1F at one end which communicates with lpassages 2a in the side castingsor heads 2, erelnafter referred to; and the body castmg also has a port 1g diametrically opposite the port 1*-, which communicates with passages 2" in the heads 2, as hereinafter explained. The chamber, 1b is preferably v olute, and increases gradually in cross section from inlet toward the outlet thereof.

The heads 2 are preferably of cast metal, f

preferably of the form shown in Figures 2, 3, 4, 6 and 7 and-are provided with passages 2a communicating with the inner ends of' i passages 3" of the"rotor 3, and passages 2b' communicating with the port 1g and the passages 3b of the rotor, as indicated in Figures 2 andV 3. The heads are bolted to the body casing 1 andthus the chambers l", 1d are tightly closed, except for the ports. Each head is provided with a central hub portion 2c in which the shaft S is journalled, and is also provided with suitable stuffing boxes in which the packingis held in the lusual manner, by means of glands'2d.

yThe passages 2", 2h in each side casting2 extend from opposite ends thereof but do not communicate with each other, as more clearly indicated in Figures 6 and 7. The passages 2", 2b are'divid'ed by a wall 2 as shown, there being no communication therebetween, each being independent of the other. The hub portions 2t of the opposed heads.2 are `stationary and fit closely into annular recesses 3a in the rotor or impeller 3 as shown in Figures 2, 3 and 5.

The rotor or impeller 3 is fixedly secured on the shaft S' so that it rotates therewith, and is preferably made of bronze, and has opposite recesses 3 in its hub into which enter the hub portions 2I of the heads 2 as shown. The. rotor shown is of the double suction type, air and water entering on both sides. The rotor has parallel sides and its side surfaces run close to the opposed surfaces of the heads 2, which close the ends of the central chamber in the body casting y asshown. In the walls of the rotor are a y equal diameter .or cross section throughout,

' 3b should be uniform in cross thisbeing desirable to enablevthe water to -push or pull out .the air eectively. The passages 3b, at their inner ends communicate with the ports or passages 2a and 2b through ports 2 and 2t respectively in the hub portlons 2f of the heads 2.

.As shown in Fi ure 1, the passage 3bx of the rotor 3 is justy eginning to, communicate with the passage'2", and the diametrically opposite passage 3" is just communicating with the passage 2, and if the rotor isoperated at high speed air will be discharged through the duct1e,and air and Water will be dischargedthrough passage 1c. The size and number of the passages in the rotor may be varied according to the' suction pressure desired to be maintained in the pump, and the size of the pump.

It will be seenfrom the drawing that the rotor is located eccentrically of the volute water chamber`l 1b, said chamber preferably gradually increasing incross section, anticlockwise around the rotor, from its inlet to outlet. The passages 3"l in the rotor are preferably curved in the direction `in which the rotor rotates as shown. The rotor is divided or separated in the .huby portion by a wall or bridge, and the only communication of the passages 2a, 2b with passages 3b is through t When the rotor is running air and water is drawn in throughY the ports 2s and 2*, water entering at 2s and air condensates entering at 2t. The air is drawn into passages 3" when they connect with port 2E; beyond this port, the centrifugal pressure of the water forces out the air into the air and water chamber 1d; arid during the further rotation o`f the rotor Water is drawn in from passage 2* through port 2s and discharged into chamber 1b. Thus due to rotation and change of positions of the passage 3b in relation `to the ports 2s and 2t, air will be ushed out by the Water into chamber ld undbr influence lof centrifugal force; and large volumes of air 'can be handled with a very small volume of water. The passages sectional area throughout for most effective results.

The water enters the rotor at a low. pres- `sure or velocity and is accelerated into the volute chamber for delivery. The air and water is separated in the volute chamber 1" the air leaving at the top entering the passages 3". At the top of the volute chamber and near the outletend thereof is a wide e ports 2F and 2t. Y

wall 1x in the body casting 1, which wall makes a close-fit with the periphery of the rotor. The centrifugal force of the water circulated in pump and rotor causes the drawing in ofthe air and also theexpulsion of same. The water is removed from the inlet to the outlet by the operation of the rotor, which being preferably double, causes such a suction when rotating. as will effectively draw in air through the inlet ports and discharge same through the outlet ports'. The air is admitted on each side of the rotor and a very large volume of air can be def livered at a low vacuum.

The rotor is hydraulically balanced, and there is no end thrust to interfere with high eiiiciency and proper operation. The air is delivered through the rotor passages at the highest portion of the pump, and the air travels upward and not downward, thus insuring greater volumetriceliiciency. No air is allowed to travel up throughthe rotor torque required to operate the pump is very low, as it is only necessary to overcome the .inertia of the rotor and -shaft which are the only moving parts. There are no close running fits which are liable to give trouble.

In the drawings, (Figures 1 to 3) the pump is shown as arranged for use as a centrifugal boiler-feed pump. In this case the air inlet 1g of the pump is connected to the heating system from which air and condensate is to be drawn by means of a check valve P and globe valve R. .The pump water inlet 1`t is also connected to a. receiver R- from which water is supplied to the pump. Air is discharged from the pump into the receiver R through the/passage 1 which is connected therewith. The receiver is open to the atmosphere. The discharge port lc of the pump is connected to thel boiler by a littilwl H which should be provided with a suitable check valve N and globe valve O. The fitting II is connected with the receiver R by a pipe I, in which isl awater circulates through pipe Irandi valve l into receiver R. While this is being' done air and water is` drawn in at inlet'lg Vwhich is'connected with the heating returns; while `water is `drawn through linlet l1t yinto'th nected with the float rod, and when the discharge Water cannot pass through the valve J the water is discharged through check valve N to the boiler, as the water, following'the line of least resistance-then goes to the boiler. ,The float is so arranged that the water in the receiver will not be lowered below the top-t of inlet 1f.' When the water is discharged to the boiler the water lowers in the receiver R permitting the float to gradually open the valve I, and allows the water to circulate back into the receiver; Vand when the float is in such position, due to the level of the water in the receiver, that the valve J is fully open, the water instead of going to the boiler through check valve N takes the line ofleast resistance and discharges back into the receiver. The receiver is\always open to the atmosphereand as air and water is separatein lthe pump'fno air is delivered to the boiler.y The air isr del-ivf -in 'the rotor and the chamber lb will be nor-.

mally filled with water. Back flow of water to the port 1g is prevented by the wall 2e. When the rotor (Figure 1) is rotated anti-clockwise the water contained in ,the passages 3b is thrown outward by centrifugal force into chamber 1". The water is drawninto the passages 3* through the portsd 2 communicating with passages 2a and thence expelled through the passages 3b into the chamber l", and any surplus water entering this chamber 1'J will pass through the passage 1, fitti'n H, and pipe I, back into the receiver R i vthe valve J be open; but if the valve J be closed such Water will be discharged to the boiler through the vcheck valve N. ,.'Ihe action of the rotor; however,

creates a suctionin the passages 2l and air and condensate is'drawn from the system R through the port 2t and passages 2 and this air and condensate is ischarged through the rotor passages 3b linto the air and water chamber 1d and conducted by pipe l le' into the receiver R. l

. Asstated, yduring the rotationof the rotor` the water drawn into the passages 3b through port 2B will-be expelled by centrifugal force intoy the chamberzlb yandl air .will take the place .of the displaced water; The outer ends .of thepassagesb are closed when 'the passages pass the lower end of'the wall ll, see Figure. 1, butthe passages 3" 'will lill with air or condensate drawn in throughA the ports 2t from passages 2". After passing the wall 1h the ai/r and condensate will be discharged into the airand water chamber 1d; communication between the latter, chamber and the chamber lb being prevented by the wall 1i oppositewall ll, with which the rotor has a close running lit. The passages 3 again become filled with water when their inner ends register with port 2B; and the above described operations arev repeated during the rotation of the', rotor.

Thenovel centrifugal vacuum'pump can be arranged for continuous operatiomorautomatic operation. by electric motor a vacuum regulator should be installed in theline'leading to 1g and connected with a suitable self starterthis meth.- od will allow the motor to stop -at'high vac.- uum and start at low vacuum. The'purnp is arranged for motor vdriv e,'belt drive,gor turbine drive, as' preferred.

'What I claim is: l

presser a casing having a rotor chamber, a water outlet, an air outlvetfay Water inlet and an air inlet; a shaft extending through said chamber; and a rotor mounted on said shaft within said chamber, and havingpassages open at both inner and outer ends and adapted to alternately register witht'he Water inlet and air inlet in each revolution of the rotor.

2. In a pump as set forth in claim 1,

means for supplying water lto the rotorA chamber to .enable the rotor tfoodischargel air from the passage" by the water under the action of centrifugal force.-

3. A centrifugal vacuum pump as set forth in claim 1 having the discharge ofd air at the top of the rotor.

4. A centrifugal ,vacuum pump comprising a casing having a. chamberffor receptipn of a rotor, a water discharge chamber ad]a cent said rotor chamber an air and water chamber adjacent the cylinder chamber, a water inlet; a condensate inlet; a rotor rotatably mounted in said rotor chamber land having radially disposed passages open at their inner and outer ends, the inner ends of said passages registering alternately withthe said inlets as the rotor rotates, and the outer endsl ofxsaid passqg'fs alternately C091" 1w municating with the water discharge charn- Ifl the pump is driven.

v, 1. In a centrifugal vacuum pump or comber and with the air and Water'char'nber y I communicate with t 5. In a pump as set forthin claim 4, means' the rotor rotates.

for supplying water to the rotor chamber to enable the rotor to discharge air from the lpassages by the Water under the action'of .centrifugal force.

6. A centrifugal vacuum pumpas setlforth in claim 4, having the discharge of air at xthe top of the rotor.l

7. A centrifugal pump comprising a cas- -ing having a chamber for reception of a rotor, a water discharge chamber at one side of said rotor chamber communicating with a water discharge passage, an air and water chamber opposite the first chamber communicating with another discharge passage; a water inlet to the casing, a condensate inlet to the casing, and ports communicating Withsaid water and condensate inlets; a rotor rotatably mounted inl said rotor chamber and having radially disposed passages open at their inner and'outer ends, the inner Aends vof said rotor passages. registering alternately with the said ports as the rotor rotates and thevouter ends of said rotor passages alternately communicating withv the water discharge chamber and with the air and water chamber as the rotor rotates.

8. Ina pump as set forth in claim 7 means for supplying. water to the rotor chamber to enable the -rotor to dscharge ,air from the passages by the water under the/action of centrifugal force. 9. In a centrifugal vacuum pump as set forth in claim 7, havingthe discharge of air at the top of the rotor.

10. `A centrifugal vacuum pump comprising a casing having a chamber for reception of a rotor, a water discharge chamber adjacent said rotor chamber, an air and water discharge chamberl adjacent the rotor chamber, a Water inlet, a condensate-inlet, passages in the casing respectively leading from the water inlet and the condensate inlet to opposite sides 'of the center of the said rotor chamber and radially disposed ports for said passages extending to points located -Within the hubv of the rotor; a rotor rotatably mounted in said rotor chamber andhaving radially disposed passages open at both their inner and outer ends, the rinner ends of said lpassages being adapted to alternatelyV register with the said ports, andthe outer ends of "said,4 channels bein die water dischar echamber and with the air and water vdgischarge chamber as the rotor rotates.

11."In a pump asset forth in claim 10,

means for supplying water tothe rotor' chamber to enable the rotor to discharge air adapted to alternately `from the passa es by the water under the action of centri ugal force.

. 12. A centrifugal vacuum pum as set forth in claim 10, having the discliarge of air atA the top of rotor.

13 A centrifugal pump of the character specified complrislng a body member having a cylindric c amber for a rotor, a volute chamber at one side of the cylindric chamber l communicating with a water discharge passage `at its larger end, an air and :water chamber at the side of the cylindric `cham` ber opposite the volute chamber and com municating with an air and water discharge passage; a water-inlet, and a condensate 1nleta pair of heads attached to the body member and closing the sides of the said cylindric chamber said heads having in-.

wardly projecting hub like portions provided with ports ontheir outer peripheries .and with passa es respectively connectin the said ports with the water inlet and wit,

the condensate inlet of the body member; a rotor mounted in said cylindric chamber and having annular recesses .on its o posite sides to receive the inwardly projecting. hub like .portions of the heads said rotor having a plurality of radiaL passages upen at both their inner and outer ends, the inner ends of said. rotor passages being adapted to alter nately register with the inlet ports and the outlet ports in the hub portions of Y said heads as the rotorrotates, and the outer ends ofA said passages alternately communicating with the volute chamber and-.with the air and Water chamber as Athe rotor rotates..

. 14. In a pump as set forth. in claim 13, means for supplying waterto the rotor' chamber to enable the rotor to discharge air froml the passages by the water -under the action of centrifugal force.

15. A centrifugal vacuum pump-as seti In testimony that I claim the-foregoing as signature.

my own, I affix my KARL G. SOMMER. 

